Microsoft is revamping its marketing strategy and may lay off hundreds of employees as a result.

Dina Bass at Bloomberg reportsSteve Ballmer is concerned that the company isn't getting enough bang for its marketing buck, and is worried about threats to Microsoft's enterprise business -- the company's core -- from newcomers like Google, Apple, and Amazon.

The job cuts are not certain, and would number in the hundreds rather than thousands, says the report.

Separately, we've also heard rumblings of layoffs coming, but these rumors come up frequently and often are not borne out.

Microsoft continually cuts employees and sometimes entire product groups, but most of these are not reported as cuts because the company's overall headcount stays the same or increases as it hires elsewhere. In 2009, it reduced headcount by about 5,000 people -- the first big reduction in its history as a public company.